Abstract: EMPLOYEE, WORKING ALONE ON 24' HIGH MOBILE SCAFFOLD, WAS INSTALLING PIPE HANGERS FOR A HEATING SYSTEM. THE MOBILE SCAFFOLD WAS MOVED BY EMPLOYEES FROM THE TOP LEVEL. THIS SCAFFOLD WAS NOT FULLY PLANKED AND DID NOT HAVE GUARD RAILS. NO ONE SAW THE ACCIDENT AND THE EMPLOYEE DOES NOT RECALL WHAT HAPPENED (A RESULT OF THE TRAUMA). IT APPEARS THAT THE EMPLOYEE WAS MOVING THE SCAFFOLD FROM THE TOP WHEN IT RAN INTO SOME CONCRETE CHIPS ON THE FINISHED FLOOR, STOPPING THE SCAFFOLD AND CAUSING THE EMPLOYEE TO GRAB A BAR JOIST FOR SUPPORT. THE EMPLOYEE LOST HIS GRIP ALMOST IMMEDIATELY AND FELL TO THE CONCRETE FLOOR BELOW. INJURIES INCLUDED A CONCUSSION, FRACTURED RIBS & VERTEBRA.